1. Field of the Invention
The present invention relates to an installation for treatment of sediments coming from stations for purification of industrial waste water. A station for pretreatment of industrial waste water has already been the object of French Pat. No. 73/27690, filed in the name of the present applicant and the Peugeot Automobile Co. on July 27, 1973.
2. Description of the Prior Art
According to that patent, the waste water, containing up to 10% of products not able to be released into the environment, are treated in an installation permitting an accelerated separation, in three phases, of the incoming water subjected to localized heating operation.
The said incoming waters contain a large quantity of oil, notably cutting liquids, drippings from treated parts and metal shavings. This constitutes the ligher phase which is recovered at the surface of the installation.
Other impurities are found in the heavier phase and recovered at the bottom of the installation in the form of sediments made up of fine particles, minerals from grinding wheel wear or various objects such as wads of plastic, shreds of cardboard or wood, etc. . . .
The middle phase, relatively homogeneous in the pretreatment installation, next undergoes complementary operations such as flocculation, centrifuging, from which results a new heavy phase charged with residues to be eliminated, and a light phase which can be returned to the environment.
The oily phase, recovered at the start of the operation, can be for the most part regenerated and recycled.